保冷结构的绝热层外不用设置防潮层。

可被碱分解或水解()

A．氢氯噻嗪

B．尼可刹米

C．两者均可发生

D．两者均不是

你所答的这张物理试卷放在水平桌面上静止时，下列的几个力中为一对平衡力的是

①试卷的重力 ②试卷对桌面的压力 ③桌面对试卷的支持力 ④桌子的重力 [ ]

A．①与②　 　

B．②与③　

C．②与④　　

D．①与③

到2008年，乡镇企业支付劳动者报酬达15830亿元，农民人均从乡镇企业获得收入1666元，比1978年的10.74元增加了150多倍，占农民人均纯收入的34.99％。这说明乡镇企业有利于

A．实现农业与第三产业的结合

B．促进农村经济结构的调整

C．加快农民致富奔小康的进程

D．保证国民经济的快速发展

To understand how astrology works, we should first take a quick look at the sky. Although the stars are at enormous distances, they do indeed give the impression of being affixed to the inner surface of a great hollow sphere surrounding the earth. Ancient people, in fact, literally believed in the existence of such a celestial sphere. As the earth, spins on its axis, the celestial sphere appears to turn about us each day, pivoting at points on a line with the earth’s axis of rotation. This daily turning of the sphere carries the stars around the sky, causing most of them to rise and set, but they, and constellations they define, maintains fixed patterns on the sphere, just as the continent of Australian maintains its shape on a spinning globe of the earth. Thus the stars were called fixed stars.

The motion of the sun along the ecliptic is, of course, merely a reflection of the revolution of the earth around the sun, but the ancients believed the earth was fixed and the sun had an independent motion of its own, eastward among the stars. The glare of sunlight hides the stars in daytime, but the ancients were aware that the stars were up there even at night, and the slow eastward motion of the sun around the sky, at the rate of about thirty degrees each month, caused different stars to be visible at night at different times of the year.

The moon, revolving around the earth each month, also has an independent motion in the sky. The moon, however, changes its position relatively rapidly. Although it appears to rise and set each day, as does nearly everything else in the sky, we can see the moon changing position during as short an interval as an hour or so. The moon’s path around the earth lies nearly in the same plane as the earth’s path around the sun, so the moon is never seen very far from the ecliptic in the sky. There are five other objects visible to the naked eye that also appear to move in respect to the fixed background of stars on the celestial sphere. These are the planets Mercury, Venus, Mars, Jupiter, and the Saturn. All of them revolve around the sun in nearly the same plane as the earth does, so they, like the moon, always appear near the ecliptic. Because we see the planets from the moving earth, however, they behave in a complicated way, with their apparent motions’ on the celestial sphere reflecting both their own independent motions around the sun and our motion as well.

According to the passage which of the following is true（）

A. A fixed star refers a star that is always stationary on the sky

B. Scientists can tell the motion of the earth from the motions of other five planets

C. Ancient people had scanty knowledge about the movement of the stars

D. All the stars on the sky can be seen all the year around

EDP的冷却使用（）

A.滑油

B.相应燃油箱内的燃油

C.液压油

D.不用冷却